/***************************************************************************/
/*                                                                         */
/*  ttobjs.c                                                               */
/*                                                                         */
/*    Objects manager (body).                                              */
/*                                                                         */
/*  Copyright 1996-2011                                                    */
/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
/*                                                                         */
/*  This file is part of the FreeType project, and may only be used,       */
/*  modified, and distributed under the terms of the FreeType project      */
/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
/*  this file you indicate that you have read the license and              */
/*  understand and accept it fully.                                        */
/*                                                                         */
/***************************************************************************/


#include <ft2build.h>
#include FT_INTERNAL_DEBUG_H
#include FT_INTERNAL_STREAM_H
#include FT_TRUETYPE_TAGS_H
#include FT_INTERNAL_SFNT_H

#include "ttgload.h"
#include "ttpload.h"

#include "tterrors.h"

#ifdef TT_USE_BYTECODE_INTERPRETER

#include "ttinterp.h"

#endif

#ifdef TT_CONFIG_OPTION_UNPATENTED_HINTING
#include FT_TRUETYPE_UNPATENTED_H
#endif

#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT

#include "ttgxvar.h"

#endif

/*************************************************************************/
/*                                                                       */
/* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
/* messages during execution.                                            */
/*                                                                       */
#undef  FT_COMPONENT
#define FT_COMPONENT  trace_ttobjs


#ifdef TT_USE_BYTECODE_INTERPRETER

/*************************************************************************/
/*                                                                       */
/*                       GLYPH ZONE FUNCTIONS                            */
/*                                                                       */
/*************************************************************************/


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_glyphzone_done                                                  */
/*                                                                       */
/* <Description>                                                         */
/*    Deallocate a glyph zone.                                           */
/*                                                                       */
/* <Input>                                                               */
/*    zone :: A pointer to the target glyph zone.                        */
/*                                                                       */
FT_LOCAL_DEF( void )
tt_glyphzone_done( TT_GlyphZone zone )
{
    FT_Memory memory = zone->memory;


    if ( memory )
    {
        FT_FREE( zone->contours );
        FT_FREE( zone->tags );
        FT_FREE( zone->cur );
        FT_FREE( zone->org );
        FT_FREE( zone->orus );

        zone->max_points = zone->n_points = 0;
        zone->max_contours = zone->n_contours = 0;
        zone->memory = NULL;
    }
}


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_glyphzone_new                                                   */
/*                                                                       */
/* <Description>                                                         */
/*    Allocate a new glyph zone.                                         */
/*                                                                       */
/* <Input>                                                               */
/*    memory      :: A handle to the current memory object.              */
/*                                                                       */
/*    maxPoints   :: The capacity of glyph zone in points.               */
/*                                                                       */
/*    maxContours :: The capacity of glyph zone in contours.             */
/*                                                                       */
/* <Output>                                                              */
/*    zone        :: A pointer to the target glyph zone record.          */
/*                                                                       */
/* <Return>                                                              */
/*    FreeType error code.  0 means success.                             */
/*                                                                       */
FT_LOCAL_DEF( FT_Error )
tt_glyphzone_new( FT_Memory memory,
                  FT_UShort maxPoints,
                  FT_Short maxContours,
                  TT_GlyphZone zone )
{
    FT_Error error;


    FT_MEM_ZERO( zone, sizeof( *zone ));
    zone->memory = memory;

    if ( FT_NEW_ARRAY( zone->org, maxPoints ) ||
         FT_NEW_ARRAY( zone->cur, maxPoints ) ||
         FT_NEW_ARRAY( zone->orus, maxPoints ) ||
         FT_NEW_ARRAY( zone->tags, maxPoints ) ||
         FT_NEW_ARRAY( zone->contours, maxContours ))
    {
        tt_glyphzone_done( zone );
    }
    else
    {
        zone->max_points = maxPoints;
        zone->max_contours = maxContours;
    }

    return error;
}

#endif /* TT_USE_BYTECODE_INTERPRETER */


/* Compare the face with a list of well-known `tricky' fonts. */
/* This list shall be expanded as we find more of them.       */

static FT_Bool
tt_check_trickyness_family( FT_String *name )
{

#define TRICK_NAMES_MAX_CHARACTERS  16
#define TRICK_NAMES_COUNT            8

    static const char trick_names[TRICK_NAMES_COUNT]
    [TRICK_NAMES_MAX_CHARACTERS + 1] =
            {
                    "DFKaiSho-SB",     /* dfkaisb.ttf */
                    "DFKaiShu",
                    "DFKai-SB",        /* kaiu.ttf */
                    "HuaTianKaiTi?",   /* htkt2.ttf */
                    "HuaTianSongTi?",  /* htst3.ttf */
                    "MingLiU",         /* mingliu.ttf & mingliu.ttc */
                    "PMingLiU",        /* mingliu.ttc */
                    "MingLi43",        /* mingli.ttf */
            };

    int nn;


    for ( nn = 0; nn < TRICK_NAMES_COUNT; nn++ )
    {
        if ( ft_strstr( name, trick_names[ nn ] ))
        {
            return TRUE;
        }
    }

    return FALSE;
}


/* XXX: This function should be in the `sfnt' module. */

/* Some PDF generators clear the checksums in the TrueType header table. */
/* For example, Quartz ContextPDF clears all entries, or Bullzip PDF     */
/* Printer clears the entries for subsetted subtables.  We thus have to  */
/* recalculate the checksums  where necessary.                           */

static FT_UInt32
tt_synth_sfnt_checksum( FT_Stream stream,
                        FT_ULong length )
{
    FT_Error error;
    FT_UInt32 checksum = 0;
    int i;


    if ( FT_FRAME_ENTER( length ))
    {
        return 0;
    }

    for ( ; length > 3; length -= 4 )
    {
        checksum += ( FT_UInt32 ) FT_GET_ULONG( );
    }

    for ( i = 3; length > 0; length--, i-- )
    {
        checksum += ( FT_UInt32 ) (FT_GET_BYTE( ) << ( i * 8 ));
    }

    FT_FRAME_EXIT( );

    return checksum;
}


/* XXX: This function should be in the `sfnt' module. */

static FT_ULong
tt_get_sfnt_checksum( TT_Face face,
                      FT_UShort i )
{
#if 0 /* if we believe the written value, use following part. */
    if ( face->dir_tables[i].CheckSum )
      return face->dir_tables[i].CheckSum;
#endif

    if ( !face->goto_table )
    {
        return 0;
    }

    if ( face->goto_table( face,
                           face->dir_tables[ i ].Tag,
                           face->root.stream,
                           NULL))
    {
        return 0;
    }

    return ( FT_ULong ) tt_synth_sfnt_checksum( face->root.stream,
                                                face->dir_tables[ i ].Length );
}


typedef struct tt_sfnt_id_rec_
{
    FT_ULong CheckSum;
    FT_ULong Length;

} tt_sfnt_id_rec;


static FT_Bool
tt_check_trickyness_sfnt_ids( TT_Face face )
{
#define TRICK_SFNT_IDS_PER_FACE   3
#define TRICK_SFNT_IDS_NUM_FACES  17

    static const tt_sfnt_id_rec sfnt_id[TRICK_SFNT_IDS_NUM_FACES]
    [TRICK_SFNT_IDS_PER_FACE] = {

#define TRICK_SFNT_ID_cvt   0
#define TRICK_SFNT_ID_fpgm  1
#define TRICK_SFNT_ID_prep  2

                    { /* MingLiU 1995 */
                            { 0x05bcf058, 0x000002e4 }, /* cvt  */
                            { 0x28233bf1, 0x000087c4 }, /* fpgm */
                            { 0xa344a1ea, 0x000001e1 }  /* prep */
                    },
                    { /* MingLiU 1996- */
                            { 0x05bcf058, 0x000002e4 }, /* cvt  */
                            { 0x28233bf1, 0x000087c4 }, /* fpgm */
                            { 0xa344a1eb, 0x000001e1 }  /* prep */
                    },
                    { /* DFKaiShu */
                            { 0x11e5ead4, 0x00000350 }, /* cvt  */
                            { 0x5a30ca3b, 0x00009063 }, /* fpgm */
                            { 0x13a42602, 0x0000007e }  /* prep */
                    },
                    { /* HuaTianKaiTi */
                            { 0xfffbfffc, 0x00000008 }, /* cvt  */
                            { 0x9c9e48b8, 0x0000bea2 }, /* fpgm */
                            { 0x70020112, 0x00000008 }  /* prep */
                    },
                    { /* HuaTianSongTi */
                            { 0xfffbfffc, 0x00000008 }, /* cvt  */
                            { 0x0a5a0483, 0x00017c39 }, /* fpgm */
                            { 0x70020112, 0x00000008 }  /* prep */
                    },
                    { /* NEC fadpop7.ttf */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0x40c92555, 0x000000e5 }, /* fpgm */
                            { 0xa39b58e3, 0x0000117c }  /* prep */
                    },
                    { /* NEC fadrei5.ttf */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0x33c41652, 0x000000e5 }, /* fpgm */
                            { 0x26d6c52a, 0x00000f6a }  /* prep */
                    },
                    { /* NEC fangot7.ttf */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0x6db1651d, 0x0000019d }, /* fpgm */
                            { 0x6c6e4b03, 0x00002492 }  /* prep */
                    },
                    { /* NEC fangyo5.ttf */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0x40c92555, 0x000000e5 }, /* fpgm */
                            { 0xde51fad0, 0x0000117c }  /* prep */
                    },
                    { /* NEC fankyo5.ttf */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0x85e47664, 0x000000e5 }, /* fpgm */
                            { 0xa6c62831, 0x00001caa }  /* prep */
                    },
                    { /* NEC fanrgo5.ttf */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0x2d891cfd, 0x0000019d }, /* fpgm */
                            { 0xa0604633, 0x00001de8 }  /* prep */
                    },
                    { /* NEC fangot5.ttc */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0x40aa774c, 0x000001cb }, /* fpgm */
                            { 0x9b5caa96, 0x00001f9a }  /* prep */
                    },
                    { /* NEC fanmin3.ttc */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0x0d3de9cb, 0x00000141 }, /* fpgm */
                            { 0xd4127766, 0x00002280 }  /* prep */
                    },
                    { /* NEC FA-Gothic, 1996 */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0x4a692698, 0x000001f0 }, /* fpgm */
                            { 0x340d4346, 0x00001fca }  /* prep */
                    },
                    { /* NEC FA-Minchou, 1996 */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0xcd34c604, 0x00000166 }, /* fpgm */
                            { 0x6cf31046, 0x000022b0 }  /* prep */
                    },
                    { /* NEC FA-RoundGothicB, 1996 */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0x5da75315, 0x0000019d }, /* fpgm */
                            { 0x40745a5f, 0x000022e0 }  /* prep */
                    },
                    { /* NEC FA-RoundGothicM, 1996 */
                            { 0x00000000, 0x00000000 }, /* cvt  */
                            { 0xf055fc48, 0x000001c2 }, /* fpgm */
                            { 0x3900ded3, 0x00001e18 }  /* prep */
                    }
            };

    FT_ULong checksum;
    int num_matched_ids[TRICK_SFNT_IDS_NUM_FACES];
    FT_Bool has_cvt, has_fpgm, has_prep;
    FT_UShort i;
    int j, k;


    FT_MEM_SET( num_matched_ids, 0,
                sizeof( int ) * TRICK_SFNT_IDS_NUM_FACES );
    has_cvt = FALSE;
    has_fpgm = FALSE;
    has_prep = FALSE;

    for ( i = 0; i < face->num_tables; i++ )
    {
        checksum = 0;

        switch ( face->dir_tables[ i ].Tag )
        {
            case TTAG_cvt:
                k = TRICK_SFNT_ID_cvt;
                has_cvt = TRUE;
                break;

            case TTAG_fpgm:
                k = TRICK_SFNT_ID_fpgm;
                has_fpgm = TRUE;
                break;

            case TTAG_prep:
                k = TRICK_SFNT_ID_prep;
                has_prep = TRUE;
                break;

            default:
                continue;
        }

        for ( j = 0; j < TRICK_SFNT_IDS_NUM_FACES; j++ )
        {
            if ( face->dir_tables[ i ].Length == sfnt_id[ j ][ k ].Length )
            {
                if ( !checksum )
                {
                    checksum = tt_get_sfnt_checksum( face, i );
                }

                if ( sfnt_id[ j ][ k ].CheckSum == checksum )
                {
                    num_matched_ids[ j ]++;
                }

                if ( num_matched_ids[ j ] == TRICK_SFNT_IDS_PER_FACE )
                {
                    return TRUE;
                }
            }
        }
    }

    for ( j = 0; j < TRICK_SFNT_IDS_NUM_FACES; j++ )
    {
        if ( !has_cvt && !sfnt_id[ j ][ TRICK_SFNT_ID_cvt ].Length )
        {
            num_matched_ids[ j ]++;
        }
        if ( !has_fpgm && !sfnt_id[ j ][ TRICK_SFNT_ID_fpgm ].Length )
        {
            num_matched_ids[ j ]++;
        }
        if ( !has_prep && !sfnt_id[ j ][ TRICK_SFNT_ID_prep ].Length )
        {
            num_matched_ids[ j ]++;
        }
        if ( num_matched_ids[ j ] == TRICK_SFNT_IDS_PER_FACE )
        {
            return TRUE;
        }
    }

    return FALSE;
}


static FT_Bool
tt_check_trickyness( FT_Face face )
{
    if ( !face )
    {
        return FALSE;
    }

    /* For first, check the face name for quick check. */
    if ( face->family_name &&
         tt_check_trickyness_family( face->family_name ))
    {
        return TRUE;
    }

    /* Type42 fonts may lack `name' tables, we thus try to identify */
    /* tricky fonts by checking the checksums of Type42-persistent  */
    /* sfnt tables (`cvt', `fpgm', and `prep').                     */
    if ( tt_check_trickyness_sfnt_ids(( TT_Face ) face ))
    {
        return TRUE;
    }

    return FALSE;
}


/* Check whether `.notdef' is the only glyph in the `loca' table. */
static FT_Bool
tt_check_single_notdef( FT_Face ttface )
{
    FT_Bool result = FALSE;

    TT_Face face = ( TT_Face ) ttface;
    FT_UInt asize;
    FT_ULong i;
    FT_ULong glyph_index = 0;
    FT_UInt count = 0;


    for ( i = 0; i < face->num_locations; i++ )
    {
        tt_face_get_location( face, i, &asize );
        if ( asize > 0 )
        {
            count += 1;
            if ( count > 1 )
            {
                break;
            }
            glyph_index = i;
        }
    }

    /* Only have a single outline. */
    if ( count == 1 )
    {
        if ( glyph_index == 0 )
        {
            result = TRUE;
        }
        else
        {
            /* FIXME: Need to test glyphname == .notdef ? */
            FT_Error error;
            char buf[8];


            error = FT_Get_Glyph_Name( ttface, glyph_index, buf, 8 );
            if ( !error &&
                 buf[ 0 ] == '.' && !ft_strncmp( buf, ".notdef", 8 ))
            {
                result = TRUE;
            }
        }
    }

    return result;
}


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_face_init                                                       */
/*                                                                       */
/* <Description>                                                         */
/*    Initialize a given TrueType face object.                           */
/*                                                                       */
/* <Input>                                                               */
/*    stream     :: The source font stream.                              */
/*                                                                       */
/*    face_index :: The index of the font face in the resource.          */
/*                                                                       */
/*    num_params :: Number of additional generic parameters.  Ignored.   */
/*                                                                       */
/*    params     :: Additional generic parameters.  Ignored.             */
/*                                                                       */
/* <InOut>                                                               */
/*    face       :: The newly built face object.                         */
/*                                                                       */
/* <Return>                                                              */
/*    FreeType error code.  0 means success.                             */
/*                                                                       */
FT_LOCAL_DEF( FT_Error )
tt_face_init( FT_Stream stream,
              FT_Face ttface,      /* TT_Face */
              FT_Int face_index,
              FT_Int num_params,
              FT_Parameter *params )
{
    FT_Error error;
    FT_Library library;
    SFNT_Service sfnt;
    TT_Face face = ( TT_Face ) ttface;


    FT_TRACE2(( "TTF driver\n" ));

    library = ttface->driver->root.library;

    sfnt = ( SFNT_Service ) FT_Get_Module_Interface( library, "sfnt" );
    if ( !sfnt )
    {
        FT_ERROR(( "tt_face_init: cannot access `sfnt' module\n" ));
        error = TT_Err_Missing_Module;
        goto Exit;
    }

    /* create input stream from resource */
    if ( FT_STREAM_SEEK( 0 ))
    {
        goto Exit;
    }

    /* check that we have a valid TrueType file */
    error = sfnt->init_face( stream, face, face_index, num_params, params );
    if ( error )
    {
        goto Exit;
    }

    /* We must also be able to accept Mac/GX fonts, as well as OT ones. */
    /* The 0x00020000 tag is completely undocumented; some fonts from   */
    /* Arphic made for Chinese Windows 3.1 have this.                   */
    if ( face->format_tag != 0x00010000L &&    /* MS fonts  */
         face->format_tag != 0x00020000L &&    /* CJK fonts for Win 3.1 */
         face->format_tag != TTAG_true)     /* Mac fonts */
    {
        FT_TRACE2(( "  not a TTF font\n" ));
        goto Bad_Format;
    }

#ifdef TT_USE_BYTECODE_INTERPRETER
    ttface->face_flags |= FT_FACE_FLAG_HINTER;
#endif

    /* If we are performing a simple font format check, exit immediately. */
    if ( face_index < 0 )
    {
        return TT_Err_Ok;
    }

    /* Load font directory */
    error = sfnt->load_face( stream, face, face_index, num_params, params );
    if ( error )
    {
        goto Exit;
    }

    if ( tt_check_trickyness( ttface ))
    {
        ttface->face_flags |= FT_FACE_FLAG_TRICKY;
    }

    error = tt_face_load_hdmx( face, stream );
    if ( error )
    {
        goto Exit;
    }

    if ( FT_IS_SCALABLE( ttface ))
    {

#ifdef FT_CONFIG_OPTION_INCREMENTAL

        if ( !ttface->internal->incremental_interface )
          error = tt_face_load_loca( face, stream );
        if ( !error )
          error = tt_face_load_cvt( face, stream );
        if ( !error )
          error = tt_face_load_fpgm( face, stream );
        if ( !error )
          error = tt_face_load_prep( face, stream );

        /* Check the scalable flag based on `loca'. */
        if ( !ttface->internal->incremental_interface &&
             ttface->num_fixed_sizes                  &&
             face->glyph_locations                    &&
             tt_check_single_notdef( ttface )         )
        {
          FT_TRACE5(( "tt_face_init:"
                      " Only the `.notdef' glyph has an outline.\n"
                      "             "
                      " Resetting scalable flag to FALSE.\n" ));

          ttface->face_flags &= ~FT_FACE_FLAG_SCALABLE;
        }

#else

        if ( !error )
        {
            error = tt_face_load_loca( face, stream );
        }
        if ( !error )
        {
            error = tt_face_load_cvt( face, stream );
        }
        if ( !error )
        {
            error = tt_face_load_fpgm( face, stream );
        }
        if ( !error )
        {
            error = tt_face_load_prep( face, stream );
        }

        /* Check the scalable flag based on `loca'. */
        if ( ttface->num_fixed_sizes &&
             face->glyph_locations &&
             tt_check_single_notdef( ttface ))
        {
            FT_TRACE5(( "tt_face_init:"
                        " Only the `.notdef' glyph has an outline.\n"
                        "             "
                        " Resetting scalable flag to FALSE.\n" ));

            ttface->face_flags &= ~FT_FACE_FLAG_SCALABLE;
        }

#endif

    }

#if defined( TT_CONFIG_OPTION_UNPATENTED_HINTING    ) && \
    !defined( TT_CONFIG_OPTION_BYTECODE_INTERPRETER )

    {
      FT_Bool  unpatented_hinting;
      int      i;


      /* Determine whether unpatented hinting is to be used for this face. */
      unpatented_hinting = FT_BOOL
        ( library->debug_hooks[FT_DEBUG_HOOK_UNPATENTED_HINTING] != NULL );

      for ( i = 0; i < num_params && !face->unpatented_hinting; i++ )
        if ( params[i].tag == FT_PARAM_TAG_UNPATENTED_HINTING )
          unpatented_hinting = TRUE;

      if ( !unpatented_hinting )
        ttface->internal->ignore_unpatented_hinter = TRUE;
    }

#endif /* TT_CONFIG_OPTION_UNPATENTED_HINTING &&
          !TT_CONFIG_OPTION_BYTECODE_INTERPRETER */

    /* initialize standard glyph loading routines */
    TT_Init_Glyph_Loading( face );

    Exit:
    return error;

    Bad_Format:
    error = TT_Err_Unknown_File_Format;
    goto Exit;
}


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_face_done                                                       */
/*                                                                       */
/* <Description>                                                         */
/*    Finalize a given face object.                                      */
/*                                                                       */
/* <Input>                                                               */
/*    face :: A pointer to the face object to destroy.                   */
/*                                                                       */
FT_LOCAL_DEF( void )
tt_face_done( FT_Face ttface )           /* TT_Face */
{
    TT_Face face = ( TT_Face ) ttface;
    FT_Memory memory;
    FT_Stream stream;
    SFNT_Service sfnt;


    if ( !face )
    {
        return;
    }

    memory = ttface->memory;
    stream = ttface->stream;
    sfnt = ( SFNT_Service ) face->sfnt;

    /* for `extended TrueType formats' (i.e. compressed versions) */
    if ( face->extra.finalizer )
    {
        face->extra.finalizer( face->extra.data );
    }

    if ( sfnt )
    {
        sfnt->done_face( face );
    }

    /* freeing the locations table */
    tt_face_done_loca( face );

    tt_face_free_hdmx( face );

    /* freeing the CVT */
    FT_FREE( face->cvt );
    face->cvt_size = 0;

    /* freeing the programs */
    FT_FRAME_RELEASE( face->font_program );
    FT_FRAME_RELEASE( face->cvt_program );
    face->font_program_size = 0;
    face->cvt_program_size = 0;

#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
    tt_done_blend( memory, face->blend );
    face->blend = NULL;
#endif
}


/*************************************************************************/
/*                                                                       */
/*                           SIZE  FUNCTIONS                             */
/*                                                                       */
/*************************************************************************/

#ifdef TT_USE_BYTECODE_INTERPRETER

/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_size_run_fpgm                                                   */
/*                                                                       */
/* <Description>                                                         */
/*    Run the font program.                                              */
/*                                                                       */
/* <Input>                                                               */
/*    size     :: A handle to the size object.                           */
/*                                                                       */
/*    pedantic :: Set if bytecode execution should be pedantic.          */
/*                                                                       */
/* <Return>                                                              */
/*    FreeType error code.  0 means success.                             */
/*                                                                       */
FT_LOCAL_DEF( FT_Error )
tt_size_run_fpgm( TT_Size size,
                  FT_Bool pedantic )
{
    TT_Face face = ( TT_Face ) size->root.face;
    TT_ExecContext exec;
    FT_Error error;


    /* debugging instances have their own context */
    if ( size->debug )
    {
        exec = size->context;
    }
    else
    {
        exec = (( TT_Driver ) FT_FACE_DRIVER( face ) )->context;
    }

    if ( !exec )
    {
        return TT_Err_Could_Not_Find_Context;
    }

    TT_Load_Context( exec, face, size );

    exec->callTop = 0;
    exec->top = 0;

    exec->period = 64;
    exec->phase = 0;
    exec->threshold = 0;

    exec->instruction_trap = FALSE;
    exec->F_dot_P = 0x10000L;

    exec->pedantic_hinting = pedantic;

    {
        FT_Size_Metrics *metrics = &exec->metrics;
        TT_Size_Metrics *tt_metrics = &exec->tt_metrics;


        metrics->x_ppem = 0;
        metrics->y_ppem = 0;
        metrics->x_scale = 0;
        metrics->y_scale = 0;

        tt_metrics->ppem = 0;
        tt_metrics->scale = 0;
        tt_metrics->ratio = 0x10000L;
    }

    /* allow font program execution */
    TT_Set_CodeRange( exec,
                      tt_coderange_font,
                      face->font_program,
                      face->font_program_size );

    /* disable CVT and glyph programs coderange */
    TT_Clear_CodeRange( exec, tt_coderange_cvt );
    TT_Clear_CodeRange( exec, tt_coderange_glyph );

    if ( face->font_program_size > 0 )
    {
        error = TT_Goto_CodeRange( exec, tt_coderange_font, 0 );

        if ( !error )
        {
            FT_TRACE4(( "Executing `fpgm' table.\n" ));

            error = face->interpreter( exec );
        }
    }
    else
    {
        error = TT_Err_Ok;
    }

    if ( !error )
    {
        TT_Save_Context( exec, size );
    }

    return error;
}


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_size_run_prep                                                   */
/*                                                                       */
/* <Description>                                                         */
/*    Run the control value program.                                     */
/*                                                                       */
/* <Input>                                                               */
/*    size     :: A handle to the size object.                           */
/*                                                                       */
/*    pedantic :: Set if bytecode execution should be pedantic.          */
/*                                                                       */
/* <Return>                                                              */
/*    FreeType error code.  0 means success.                             */
/*                                                                       */
FT_LOCAL_DEF( FT_Error )
tt_size_run_prep( TT_Size size,
                  FT_Bool pedantic )
{
    TT_Face face = ( TT_Face ) size->root.face;
    TT_ExecContext exec;
    FT_Error error;


    /* debugging instances have their own context */
    if ( size->debug )
    {
        exec = size->context;
    }
    else
    {
        exec = (( TT_Driver ) FT_FACE_DRIVER( face ) )->context;
    }

    if ( !exec )
    {
        return TT_Err_Could_Not_Find_Context;
    }

    TT_Load_Context( exec, face, size );

    exec->callTop = 0;
    exec->top = 0;

    exec->instruction_trap = FALSE;

    exec->pedantic_hinting = pedantic;

    TT_Set_CodeRange( exec,
                      tt_coderange_cvt,
                      face->cvt_program,
                      face->cvt_program_size );

    TT_Clear_CodeRange( exec, tt_coderange_glyph );

    if ( face->cvt_program_size > 0 )
    {
        error = TT_Goto_CodeRange( exec, tt_coderange_cvt, 0 );

        if ( !error && !size->debug )
        {
            FT_TRACE4(( "Executing `prep' table.\n" ));

            error = face->interpreter( exec );
        }
    }
    else
    {
        error = TT_Err_Ok;
    }

    /* save as default graphics state */
    size->GS = exec->GS;

    TT_Save_Context( exec, size );

    return error;
}

#endif /* TT_USE_BYTECODE_INTERPRETER */


#ifdef TT_USE_BYTECODE_INTERPRETER

static void
tt_size_done_bytecode( FT_Size ftsize )
{
    TT_Size size = ( TT_Size ) ftsize;
    TT_Face face = ( TT_Face ) ftsize->face;
    FT_Memory memory = face->root.memory;


    if ( size->debug )
    {
        /* the debug context must be deleted by the debugger itself */
        size->context = NULL;
        size->debug = FALSE;
    }

    FT_FREE( size->cvt );
    size->cvt_size = 0;

    /* free storage area */
    FT_FREE( size->storage );
    size->storage_size = 0;

    /* twilight zone */
    tt_glyphzone_done( &size->twilight );

    FT_FREE( size->function_defs );
    FT_FREE( size->instruction_defs );

    size->num_function_defs = 0;
    size->max_function_defs = 0;
    size->num_instruction_defs = 0;
    size->max_instruction_defs = 0;

    size->max_func = 0;
    size->max_ins = 0;

    size->bytecode_ready = 0;
    size->cvt_ready = 0;
}


/* Initialize bytecode-related fields in the size object.       */
/* We do this only if bytecode interpretation is really needed. */
static FT_Error
tt_size_init_bytecode( FT_Size ftsize,
                       FT_Bool pedantic )
{
    FT_Error error;
    TT_Size size = ( TT_Size ) ftsize;
    TT_Face face = ( TT_Face ) ftsize->face;
    FT_Memory memory = face->root.memory;
    FT_Int i;

    FT_UShort n_twilight;
    TT_MaxProfile *maxp = &face->max_profile;


    size->bytecode_ready = 1;
    size->cvt_ready = 0;

    size->max_function_defs = maxp->maxFunctionDefs;
    size->max_instruction_defs = maxp->maxInstructionDefs;

    size->num_function_defs = 0;
    size->num_instruction_defs = 0;

    size->max_func = 0;
    size->max_ins = 0;

    size->cvt_size = face->cvt_size;
    size->storage_size = maxp->maxStorage;

    /* Set default metrics */
    {
        TT_Size_Metrics *metrics = &size->ttmetrics;


        metrics->rotated = FALSE;
        metrics->stretched = FALSE;

        /* set default compensation (all 0) */
        for ( i = 0; i < 4; i++ )
        {
            metrics->compensations[ i ] = 0;
        }
    }

    /* allocate function defs, instruction defs, cvt, and storage area */
    if ( FT_NEW_ARRAY( size->function_defs, size->max_function_defs ) ||
         FT_NEW_ARRAY( size->instruction_defs, size->max_instruction_defs ) ||
         FT_NEW_ARRAY( size->cvt, size->cvt_size ) ||
         FT_NEW_ARRAY( size->storage, size->storage_size ))
    {
        goto Exit;
    }

    /* reserve twilight zone */
    n_twilight = maxp->maxTwilightPoints;

    /* there are 4 phantom points (do we need this?) */
    n_twilight += 4;

    error = tt_glyphzone_new( memory, n_twilight, 0, &size->twilight );
    if ( error )
    {
        goto Exit;
    }

    size->twilight.n_points = n_twilight;

    size->GS = tt_default_graphics_state;

    /* set `face->interpreter' according to the debug hook present */
    {
        FT_Library library = face->root.driver->root.library;


        face->interpreter = ( TT_Interpreter )
                library->debug_hooks[ FT_DEBUG_HOOK_TRUETYPE ];
        if ( !face->interpreter )
        {
            face->interpreter = ( TT_Interpreter ) TT_RunIns;
        }
    }

    /* Fine, now run the font program! */
    error = tt_size_run_fpgm( size, pedantic );

    Exit:
    if ( error )
    {
        tt_size_done_bytecode( ftsize );
    }

    return error;
}


FT_LOCAL_DEF( FT_Error )
tt_size_ready_bytecode( TT_Size size,
                        FT_Bool pedantic )
{
    FT_Error error = TT_Err_Ok;


    if ( !size->bytecode_ready )
    {
        error = tt_size_init_bytecode(( FT_Size ) size, pedantic );
        if ( error )
        {
            goto Exit;
        }
    }

    /* rescale CVT when needed */
    if ( !size->cvt_ready )
    {
        FT_UInt i;
        TT_Face face = ( TT_Face ) size->root.face;


        /* Scale the cvt values to the new ppem.          */
        /* We use by default the y ppem to scale the CVT. */
        for ( i = 0; i < size->cvt_size; i++ )
        {
            size->cvt[ i ] = FT_MulFix( face->cvt[ i ], size->ttmetrics.scale );
        }

        /* all twilight points are originally zero */
        for ( i = 0; i < ( FT_UInt ) size->twilight.n_points; i++ )
        {
            size->twilight.org[ i ].x = 0;
            size->twilight.org[ i ].y = 0;
            size->twilight.cur[ i ].x = 0;
            size->twilight.cur[ i ].y = 0;
        }

        /* clear storage area */
        for ( i = 0; i < ( FT_UInt ) size->storage_size; i++ )
        {
            size->storage[ i ] = 0;
        }

        size->GS = tt_default_graphics_state;

        error = tt_size_run_prep( size, pedantic );
        if ( !error )
        {
            size->cvt_ready = 1;
        }
    }

    Exit:
    return error;
}

#endif /* TT_USE_BYTECODE_INTERPRETER */


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_size_init                                                       */
/*                                                                       */
/* <Description>                                                         */
/*    Initialize a new TrueType size object.                             */
/*                                                                       */
/* <InOut>                                                               */
/*    size :: A handle to the size object.                               */
/*                                                                       */
/* <Return>                                                              */
/*    FreeType error code.  0 means success.                             */
/*                                                                       */
FT_LOCAL_DEF( FT_Error )
tt_size_init( FT_Size ttsize )           /* TT_Size */
{
    TT_Size size = ( TT_Size ) ttsize;
    FT_Error error = TT_Err_Ok;

#ifdef TT_USE_BYTECODE_INTERPRETER
    size->bytecode_ready = 0;
    size->cvt_ready = 0;
#endif

    size->ttmetrics.valid = FALSE;
    size->strike_index = 0xFFFFFFFFUL;

    return error;
}


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_size_done                                                       */
/*                                                                       */
/* <Description>                                                         */
/*    The TrueType size object finalizer.                                */
/*                                                                       */
/* <Input>                                                               */
/*    size :: A handle to the target size object.                        */
/*                                                                       */
FT_LOCAL_DEF( void )
tt_size_done( FT_Size ttsize )           /* TT_Size */
{
    TT_Size size = ( TT_Size ) ttsize;


#ifdef TT_USE_BYTECODE_INTERPRETER
    if ( size->bytecode_ready )
    {
        tt_size_done_bytecode( ttsize );
    }
#endif

    size->ttmetrics.valid = FALSE;
}


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_size_reset                                                      */
/*                                                                       */
/* <Description>                                                         */
/*    Reset a TrueType size when resolutions and character dimensions    */
/*    have been changed.                                                 */
/*                                                                       */
/* <Input>                                                               */
/*    size :: A handle to the target size object.                        */
/*                                                                       */
FT_LOCAL_DEF( FT_Error )
tt_size_reset( TT_Size size )
{
    TT_Face face;
    FT_Error error = TT_Err_Ok;
    FT_Size_Metrics *metrics;


    size->ttmetrics.valid = FALSE;

    face = ( TT_Face ) size->root.face;

    metrics = &size->metrics;

    /* copy the result from base layer */
    *metrics = size->root.metrics;

    if ( metrics->x_ppem < 1 || metrics->y_ppem < 1 )
    {
        return TT_Err_Invalid_PPem;
    }

    /* This bit flag, if set, indicates that the ppems must be       */
    /* rounded to integers.  Nearly all TrueType fonts have this bit */
    /* set, as hinting won't work really well otherwise.             */
    /*                                                               */
    if ( face->header.Flags & 8 )
    {
        metrics->x_scale = FT_DivFix( metrics->x_ppem << 6,
                                      face->root.units_per_EM );
        metrics->y_scale = FT_DivFix( metrics->y_ppem << 6,
                                      face->root.units_per_EM );

        metrics->ascender =
                FT_PIX_ROUND( FT_MulFix( face->root.ascender, metrics->y_scale ));
        metrics->descender =
                FT_PIX_ROUND( FT_MulFix( face->root.descender, metrics->y_scale ));
        metrics->height =
                FT_PIX_ROUND( FT_MulFix( face->root.height, metrics->y_scale ));
        metrics->max_advance =
                FT_PIX_ROUND( FT_MulFix( face->root.max_advance_width,
                                         metrics->x_scale ));
    }

    /* compute new transformation */
    if ( metrics->x_ppem >= metrics->y_ppem )
    {
        size->ttmetrics.scale = metrics->x_scale;
        size->ttmetrics.ppem = metrics->x_ppem;
        size->ttmetrics.x_ratio = 0x10000L;
        size->ttmetrics.y_ratio = FT_MulDiv( metrics->y_ppem,
                                             0x10000L,
                                             metrics->x_ppem );
    }
    else
    {
        size->ttmetrics.scale = metrics->y_scale;
        size->ttmetrics.ppem = metrics->y_ppem;
        size->ttmetrics.x_ratio = FT_MulDiv( metrics->x_ppem,
                                             0x10000L,
                                             metrics->y_ppem );
        size->ttmetrics.y_ratio = 0x10000L;
    }

#ifdef TT_USE_BYTECODE_INTERPRETER
    size->cvt_ready = 0;
#endif /* TT_USE_BYTECODE_INTERPRETER */

    if ( !error )
    {
        size->ttmetrics.valid = TRUE;
    }

    return error;
}


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_driver_init                                                     */
/*                                                                       */
/* <Description>                                                         */
/*    Initialize a given TrueType driver object.                         */
/*                                                                       */
/* <Input>                                                               */
/*    driver :: A handle to the target driver object.                    */
/*                                                                       */
/* <Return>                                                              */
/*    FreeType error code.  0 means success.                             */
/*                                                                       */
FT_LOCAL_DEF( FT_Error )
tt_driver_init( FT_Module ttdriver )     /* TT_Driver */
{

#ifdef TT_USE_BYTECODE_INTERPRETER

    TT_Driver driver = ( TT_Driver ) ttdriver;


    if ( !TT_New_Context( driver ))
    {
        return TT_Err_Could_Not_Find_Context;
    }

#else

    FT_UNUSED( ttdriver );

#endif

    return TT_Err_Ok;
}


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_driver_done                                                     */
/*                                                                       */
/* <Description>                                                         */
/*    Finalize a given TrueType driver.                                  */
/*                                                                       */
/* <Input>                                                               */
/*    driver :: A handle to the target TrueType driver.                  */
/*                                                                       */
FT_LOCAL_DEF( void )
tt_driver_done( FT_Module ttdriver )     /* TT_Driver */
{
#ifdef TT_USE_BYTECODE_INTERPRETER
    TT_Driver driver = ( TT_Driver ) ttdriver;


    /* destroy the execution context */
    if ( driver->context )
    {
        TT_Done_Context( driver->context );
        driver->context = NULL;
    }
#else
    FT_UNUSED( ttdriver );
#endif

}


/*************************************************************************/
/*                                                                       */
/* <Function>                                                            */
/*    tt_slot_init                                                       */
/*                                                                       */
/* <Description>                                                         */
/*    Initialize a new slot object.                                      */
/*                                                                       */
/* <InOut>                                                               */
/*    slot :: A handle to the slot object.                               */
/*                                                                       */
/* <Return>                                                              */
/*    FreeType error code.  0 means success.                             */
/*                                                                       */
FT_LOCAL_DEF( FT_Error )
tt_slot_init( FT_GlyphSlot slot )
{
    return FT_GlyphLoader_CreateExtra( slot->internal->loader );
}


/* END */
